"M.K. MORSE" HOLE SAWS Cutting Diam: 1 3/8" Applicable Materials: Wood, Plastic, Most Metals . Cutting Depth: 1 1/2" Cutting Edge Material: HSS Quantity: 1 per box . Backer, cutting edge and cap work together to provide faster, longer-lasting cutting action . Bi-metal design bonds M3 cutting edge to fatigue resistant backer . Positive rake teeth clear chips better for longer life and easier cutting . Teeth stay sharper and make smoother cuts.